NEET Physics Nuclei Questions Solved

The electric potential between a proton and an electron is given by $\mathrm{V}={\mathrm{V}}_{0}\mathrm{ln}\frac{\mathrm{r}}{{\mathrm{r}}_{0}}$ where ${\mathrm{r}}_{0}$ is a constant. Assuming Bohr’s model to be applicable, write variation of ${\mathrm{r}}_{\mathrm{n}}$ with n, n being the principal quantum number

(a) ${\mathrm{r}}_{\mathrm{n}}\propto \mathrm{n}$            (b)  ${\mathrm{r}}_{\mathrm{n}}\propto 1/\mathrm{n}$
(c) ${\mathrm{r}}_{\mathrm{n}}\propto {\mathrm{n}}^{2}$           (d) ${\mathrm{r}}_{\mathrm{n}}\propto 1/{\mathrm{n}}^{2}$